The field of the disclosure relates generally to filling, draining, and venting tanks, and, more particularly, to a bung plug and extractor system for use in exchanging fluid with pressurized tanks.
At least some known tanks, such as known propellant and pressurant tanks used within liquid rockets, for example, include one or more tank ports that enable exchanges of fluid with the tank, such as occurs when filling, draining, or venting the tank. The fluid may be a gas and/or a liquid. Such fluid exchange operations must be enabled while the tank contents are under pressure, but without spillage or leakage of the fluid. Fluid transfer may be further complicated if the fluid is toxic, highly volatile (flammable or explosive), and/or in a cryogenic state. To enable fluid transfer, at least some known tanks include a fill/drain port and a vent port, with dedicated high-pressure fill/drain valves and vent valves internal or external to the tank and between the tank and the respective ports, such that only a simple hose connection to each tank port is needed. However, at least some known fill/drain valves and vent valves add considerable weight, cost, and component volume to the pressurized tank. Moreover, the reliability of such valves may be limited.